I don't care how much you earn. _________ is, I think, whether weare happy that really matters.
| A．It | B．Which |
| C．What | D．How |
Not only his parents but also his sister ________ the museum.
A. are going to B. is going to c. are going D. is going
This book is worth _____.
| A．to read it | B．reading it | C．reading | D．to read |
We should do ___ the teacher told us.
| A．because | B．like | C．as | D．since |
The number of the people in the world ______ growing faster and faster.
A. is b. are C. have D. were
I’m sorry to have kept you ________ for a long time.
A. wait b. to wait c. waiting D. to be waiting